It is considered to be cryptographically far too weak to provide any security against brute-force attacks by modern, commodity personal computers.
[2] Linux distributions generally do not include a Unix compatible version of the crypt command.
Enhanced symmetric encryption utilities are available for Linux (and should also be portable to any other Unix-like system) including mcrypt and ccrypt.
Bob Baldwin's public domain Crypt Breaker's Workbench, which was written in 1984-1985, is an interactive tool that provides successive plaintext guesses that must be corrected by the user.
[6] Peter Selinger's unixcrypt-breaker uses a simple statistical model similar to a dictionary-attack that takes a set of plain texts as input and processes it to guess plausible plaintexts, and does not require user interaction.